如何在ActionScript 3中将"Null"(真正的姓氏!)传递给SOAP Web服务？

import mx.rpc.soap.WebService;

var ws:WebService = new WebService();
ws.wsdl = "http://example.com/your_web_service.wsdl";
ws.loadWSDL();

var request:Object = new Object();
request.yourParameter = null;

ws.yourOperation(request);

public class YourWebService {
    public void yourOperation(Object request) {
        if (request.yourParameter == null) {
            // 处理空值情况
        } else {
            // 正常处理
        }
    }
}

public class YourWebService {
    public String yourOperation(Object request) {
        if (request.yourParameter == null) {
            return "Null";
        } else {
            // 正常处理
            return "处理结果";
        }
    }
}

ws.yourOperation.addEventListener("result", function(event:ResultEvent):void {
    var result:String = event.result as String;
    if (result == "Null") {
        // 处理空值情况
    } else {
        // 正常处理
    }
});